Cockpit lighting has been the subject of considerable discussion. In military aviation, red lighting was long used in the cockpit and pilots were required to wear red goggles for a certain period of time before night flight. These precautions for night adaptation were necessary because pilots who needed to spot enemy aircraft frequently flew from inadequately lighted airports and navigated by vision more than by instruments.
With the advent of adequately lighted airports and the general use of radio for navigation, “night vision” actually became less important. The tendency now is toward more complete illumination of the cockpit, with white light used more than red. Problems such as improper fuel selection and errors in course plotting or chart reading are much more significant now than the loss of night vision. Still, you should be familiar with a few facts about visual adaptation during night flying.
1. Your eyes need about 30 minutes to adjust to maximum night efficiency after exposure to bright light.
2. Bright lights (such as landing lights) knock out night vision, requiring you to “night-adapt” all over again to regain maximum night vision. Closing one eye when you are briefly exposed to bright light (while map reading, for instance) may protect that eye so it need not re-adapt.
3. Lightning flashes knock out night vision. Therefore, near storm clouds, turn up the cockpit lights to see your instruments properly.
4. Remember to remove your sunglasses after sunset, or you may find yourself flying in “instrument conditions” when actually the ceiling and visibility are normal.